found in the Vicinity of Manchester. 349 



further, on St. George's Road, the coal measures appear at the 

 pits of E. Buckley, Esq. According to the regular range of 

 the strata, we ought to find the Ardwick limestones exposed 

 between these two points, but they do not appear : on an ex- 

 amination of the locality, the reason is obvious; the red sand- 

 stone ranges unconformably with the coal strata, overlying 

 their outcropping edges, and thus completely covering up that 

 portion in which the limestones ought to have been met with. 

 The locality is a very difficult one to examine and decide upon, 

 from the want of sections at the most important points; but as 

 there is no doubt of the sandstone overlying the edges of the 

 coal strata, and the dip of the latter being such as would carry 

 their upper portions beneath where we find the red sandstone 

 on the surface, the apparent deficiency is accounted for. 



Sect. VIII. Organic Remains. 



The fossil remains of this series of limestones, with one or 

 two exceptions, are neither numerous nor exhibiting much 

 variety, although they are of a peculiar character : these we 

 will examine in their separate classes, and, then from their 

 evidences endeavour to draw some conclusion as to the nature 

 of the limestones and the circumstances under which they 

 were deposited. 



1. Vegetable Remains. 



These are not so numerous as, from the connexion of the 

 sti'ata with the coal measures, might have been expected, al- 

 though further investigation will doubtless bring new deposits 

 to light. 



Stigmariafcoides is found abundantly in the seam of coal im- 

 mediately below the black bass. The coal appears to have been 

 entirely composed of this plant, as it is the only one I have hi- 

 therto found in connexion with it. The character this extraor- 

 dinary plant must have given to the primaeval world cannot fail 

 to have been highly singular, as from the highest to the lowest 

 coals of this group of strata its abundance generally forms a 

 conspicuous feature, whilst its range appears to have been 

 almost universal. In a seam of indurated blue clay, below the 

 black bass, the leaves of Stigmaria are found in the greatest 

 profusion. The same is observed in a reddish clay on the bed 

 of the Medlock, much lower in the series. 



In the blue clay, immediately above the black bass, I found 

 a small and beautiful species of Sphenophyllum, much like 

 Sphcn. erosum, but with broader leaflets, and fewer in each 

 whorl. In the same clay occurred fragments of a species of 

 Pecopteris and also of an Equisetum, neither of which I was 

 able to preserve. 



In working through a narrow passage of one of the mines, 



